Over the last few months I have noticed a dull pain that develops in the area of my left shoulder blade while about an hour or hour and a half into my rides. I've only noticed it on my road and cyclocross bike, but I haven't been on my MTB much with all the rain.

I haven't made any adjustments to my bikes that would effect my position so I'm a little puzzled. Any ideas?

Your body may be telling you that your road bike and cycle cross bikes with the traditional drop position may not be the best position for your aging body. You should look at doing some adjustments of the handlebar set up, shorter and taller stem positioning may help decrease the load on your shoulders.

I was experiencing shoulder, neck pain and the DDD (see post below) from my daily 25 mile round trip commuting on my road bike that previously -did not bother me for years but once I got north of the 40 mark, the body and the road bike were no longer accommodating. I went through physical therapy trying to get rid the progressively worsening muscle spasm, neck and shoulder pain that was coming with my daily cycle commutes. See my article at http://www.bikeroute.com/Recumbents/BentMedBenefits.php to get the rest of the story. Go recumbent if the above tricks down work. Keep your mountain bike they rule off road and as you have found the different riding position is more favorable for you.

Thanks for the info. I will look into adjusting my handlebar position. Hopefully my age isn't making that big of an impact as I am 29 years old. I was hoping to wait another 40 to 50 years to switch to the recumbent